Existing ontology reasoners are optimized to process relatively small, consistent and unambiguous knowledge bases (KBs). However, many KBs tend to be large, as well as inconsistent and ambiguous. This is especially true for ontologies that are derived from text analytic programs or programs that analyze the relationship between individuals from unstructured information. Collaborative development of the ontology also gives rise to inconsistencies, as does integration of different ontologies. As such, it there exists a need to reason over ontologies despite the presence of inconsistencies and/or uncertainty.